Vacuum tube



July 27, 1926. 1,594,179

S.LJDEVVE VACUUM TUBE Filed August 26, 1921 l `,A AVMENTUR BY j . aten'ted July' rence SIEGMUND LDEWE, F BERLN, GERMANY, ASSIGNOR T0 WESTINGHOUSE ELEGTRIC MMFEACTURNG COMPANY, A CORPORATION 0F PENNSYLVANIA.

VACUUM TUBE.

Application flied August 26, 1921, Serial No.. 495,779, and in Germany April 20, 1918.

(aannam nanna THE PROVISIONS or THE Aer or MARCH 3, 1921, 41 STAT. L', 1313.)

lThis application relates to space-current devices, and particularly to devices in which a vacuum tube is used with a source of direct current for generating oscillations.

It is an object of this invention to make use of the effect which one space current produces upon a second current when the two space-current paths are distinct over portions of their length and have the same space in common through the remaining'portion.

It is a further object of my invention to provide an arrangement by which the interaction of two-space currents, which either intersect or merge, will produce a periodicy transfer of energy, from the circuit including one space-current path, to the circuit in`- cluding the other space-current path, and

back again.

It is a further object of my invention to provide a vacuum-tube device having a plurality of cathodes and at least as many anodes and thus affording a plurality of space-current paths, partly distinct and partly through a portion of the device common to the several paths.

Other objects of my invention, and details of the construction will be apparent from the drawings and the following description.

Referring now to the drawings, Fig. 1 illustrates a proposed form of vacuum tube and circuit connections therefor adapted to produce continuous wave oscillations;

Fig. 2 is a modification of therrangement illustrated in Fig. 1;

Fig. 3 illustrates a vacuum .tube oscillation generator operatively connected to a work circuit;

Fig. 4 illustrates a modified form of vacuum tube having a plurality of current paths which exert reciprocal influences upon one another;

Fig. 5 is a modification of the structure i shown in Fig. 4, in which the heated ilament cathodes are replaced by mercury wells.

In the form of the invention illustrated in Fig. 1, the vacuum tube 1 is provided with four arms which merge into a central space. The cathodes 2 and 3 are located in two adjacent arms. The anodes 4 and 5 are located in thev arms opposite, respectively, to the arms containing the cathodes 2 and 3. A battery 6 supplies heating current to the cathodes 2 and 3 in series.

A battery 7 supplies current to the two plate circuits in parallel. One of these plate circuits includes the anode 4, the coil 11, the condenser 9 and the cathode 2, in series, the

connection to the battery being between the coil and the condense-r. The other plate circuit includes the anode 5, `the coil 10, the condenser 8 and the cathode 3, in series, the connection to the battery being also between the coil and the condenser in this case also.

In the operation of the device, a space current flows from the anode 4 to the cathode 2, producing a current through the coil 11. A space current also flows from the anode 5 to the cathode 3, producing a current in the coil 10. These two space currents intersect each other and exercise an influence on each other. An increase in the space current to the cathode 2 causes a diminution in the space current to the cathode 3.and, reciprocally, an increase in the space lcurrent to the cathode 3 causes a diminution in the space current to the cathode 2. It will be observed, however, that the inductive relation between the coils 10 and 11 also causes the 'change in the current in one circuit to produce a change in the current in the other circuit. Moreover, because these coils have considerable inductance, the changes in question will progress beyond the Aequilibrium point and the system will, therefore, oscillate.

The energy for the oscillations is obtained from the battery 7. Their frequency is determined by the constants of the circuit, which include the inductance of the transformer 10-11 and the capacity of the condenser 8, for one circuit, and ofthe condenser 9', for the other circuit. The energy of the oscillations may be taken from-the oscillating system for useful work in any desired way. Many ways. of` doing this are known to those skilled in the art. For example, a third coil, inductively related to the coils 10 and 11, may deliver current to the load. Again, either of the condensers 9 and 8 may be replaced by the antenna of a radiating system.

In the form illustrated in Fig. 2, the vacuum tube is, as before, provided with two lli cathodes 2 and 3 and two anodes 4 and 5. For the sake of simplicity, the heating circuit Jfor the cathodes is omitted from this figure. The cathode 2 and the anode 5 are connected together and an inductor 12 is 1nscrted between said connection and the condcnsers 8 and 9. The sides of the condensers not connected to the inductor 12 are connected, respectively to the cathode 3 and the anode 4. The connection to the cathode includes a coil 14, in inductive relation to a coil 13, in the connection to the anode 4. The coils 13 and 14 are inductively related, the direction of coupling being such that, at the time the anode 4 is delivering current, a positive potential is impressed upon the cathode 3. Consequently, there is no current from anode 4 to cathode 3.

The source of energy represented by the signs -land is connected to the system through a pair of choke coils 15 and 16. the connection being, in each case, between a condenser and the coil with which it is associated.

In the operation of the device shown in Fig. 2, current from the anode 4 to the cathode 2 influences current from the anode 5 to the cathode 3. If either of these currents increases there is a tendency for the other to decrease. Consider the moment at which the condenser 9 has been fully charged and begins to discharge. The discharge of this condenser adds to the current between the anode 4 and the cathode 2. This will diminish the current between anode 5 and cathode 3 which is the current tending to charge the condenser 8. It will, therefore, be seen that if any irregularity gives rise to a dierence in the charges upon the two condens/ers, oscillations will be set up which, because of the energy supplied through the coils 15 and 16, will build up to a maximum. The maximum is reached when the charge upon either condenser is equal to the difference of potential impressed upon coils 15 and 16.

The energy of the oscillations may be delivered to the load in ways with which the art is familiar. There may, for example, be an output circuit inductively connected to the coil 12 or either of the condensers 8 and 9 may be an antenna.

In the form of the invention illustratedin Fig. 3, two cathodes 2 and 3 are provided in a vacuum tube, having such a form that throughout the greater length of the spacecurrents paths, the electron streams are free to mingle. Two anodes 4 and 5 are provided at the other end of the vacuum tube from the cathodes. Preferably, the cathodes and anodes are arranged symmetrically about the mid-plane of the tube.

The cathodes are maintained at the necessary temperature by means of heating bat teries 6. The anodes are connected to the cathodes upon the same sideof the midplane, the connection being in each case through a source of potential. The sources are illustrated as two batteries 21 and 21 but it willbe apparent to those skilled in the art that a single battery may be used instead of the two batteries, if desired.

An anode 17 is located in the mid-plane of the device at the same end of the tube as anodes 4 and 5. The output circuit is connected to this anode. It may consist of two conductors on opposite sides of a condenser 18, or there may be a single conductor and the side of the condenser 18 which is not connected to the anode 17 be connected to ground.

In the operation of this device, the space current, normally divides, going from the anode 17 to the two cathodes 2 and 3. When the system oscillates, the electron stream swings back and forth between anodes 4 and l5, causing periodic variations in the current to the anode 17. These periodic variations give rise to the output which is delivered to the condenser 18 and so to the output circuit.

In the form of the invention illustrated in Fig. 4, the two space current paths are in the direction of the arrows 22 and 23. The inter-action between the space currents occurs between the two cathodes occupying the middle portion of the tube.

Fig. 5 illustrates the application of the invention to a device containing mercury or other volatile cathodes. The space-current path from the left-hand anode extends to the right-hand cathode and that from the right-hand anode extends to the left-hand cathode. Thus the space-current paths cross each other. When one space Vcurrent increases, the other diminishes as in the form described at greater length.

It will be obvious to those skilled in the art that the invention herein described can be applied to systems requiring multi-phase oscillating currents; in which application, instead of two space currents reciprocally influencing one another, there will be a larger number.

Other forms of the invention will be apparent to those skilled in the art. The detailed description of the small number of forms speciically illustrated herein is not intended to limit the invention to those forms. No limitation other than that required by the prior art and explicitly recited in the claims is intended.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is:

1. The method of controlling a thermion current between two electrodes which comprises producing a second thermion current adjacent said thermion current to be con- III trolled and varying said second thermion current.

2. The method of controlling a thermion current between two electrodes which comprises producing a second thermion current which envelops one of said electrodes and varyin said second thermion current.

3. Tigre method of controlling a thermion current between two electrodes which comprises producing a second thermion current the path of which crosses the path of the thermion current to be controlled and varying said second thermion current.

4. A generator of oscillating current energy comprisin two associated tuned 'circuits each circult including a thermion current path anda source of thermion current, ysaid thermion current paths intersecting, and means for adjusting the `:oupling between said circuits. y

5. A generatorof oscillating current energy comprising a thermion -current discharge device having two cathodes and two emissivity cathodes.

anodes, one cathode and one anode bein electrically connected, a circuit from sai ergy consuming device, a capacity and an inductance, said inductances being coupled, and a source of energy connected across said capacities.

6. An alternating current indicating instrument comprising a vacuum tube having two electron emitting cathodes, a circuit between said cathodes includin an indicating instrument and a source of high frequency current, and means for varying the electron of one of said electron emitting In testimony whereof I aix my signature.

DR. SIEGM'UND LOEWE. 

